Hydrophobic oxides of metals and for metalloids

ABSTRACT

Highly dispersed metal or metalloid oxides are rendered hydrophobic by 
     I. contacting such oxide particles while in the form of an aerogel with a dry inert gas stream in a fluidizing bed at a temperature from 600° to 1000° C and at atmospheric pressure for a period of less than 60 seconds to render the particles absolutely dry and thus activate them; 
     Ii. charging the resultant dried and activated particles in a fluidizing bed with at least one gas-phase organosilicon compound selected from the group consisting of (a) linear organopolysiloxanes (b) cyclic organopolysiloxanes (c) a mixture of both types of siloxanes and (d) a mixture of any of the substances (a)-(c) with an organohalogenosilane at a temperature in the range from 25° to 650° C; 
     Iii. causing said charged particles to react with the organosilicon compounds at a temperature from 35° to 650° C; and 
     Iv. finally treating the reaction product with an inert gas stream in a fluidizing bed at temperatures from 500° to 125° C.

REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 241,761, filed onApr. 6, 1972 now U.S. Pat. No. 3,920,865 which, in turn, is acontinuation-in-part of the abandoned application Ser. No. 23,330 by thesame inventors in respect of Process of Hydrophobizing Highly DispersedOxides and filed on Mar. 27, 1970.

BACKGROUND OF THE INVENTION

This invention relates to a process for product obtained byhydrophobizing highly dispersed oxides, mixed oxides and oxide mixturesof metals and/or metalloids by treating the oxide particles withvolatilizable organosilicon compounds in the gas phase.

It is known to hydrophobize highly dispersed oxides (active fillers)which have been obtained by reaction of metal or metalloid compounds orvolatile compounds thereof in vapor form at elevated temperatures in thepresence of a hydrolyzing and possibly also an oxidizing agent. Theoxides in this process are rendered hydrophobic by reaction with ahalogen containing inorganic or organic silicon compound.

Oxide-aerogels usually are made by subjecting volatile compounds ofmetal or metalloids, particularly the halides or gas mixtures containingthe same, in the gaseous phase to the hydrolyzing influence of watervapor, whereby the resulting oxides, present in the aerosol state, formaerogels and then isolating these products from the easily condensed,gaseous reaction products at a temperature above their dew points. Thewater vapor forming gas mixtures can consist of combustible,particularly hydrogen containing gas mixtures or compositions which formsuch mixtures and also of non-combustible, preferably oxygen containinggases. The oxides, obtained have a primary particle size of less than150mμ. As starting materials for this process, there may be usedvolatile halides and preferably chlorides and fluorides.

In the preparation of mixed oxides, different metals or metalloids orcompounds thereof which are volatile are introduced simultaneously asgaseous mixtures into the thermal reaction, so as to cause the oxides toseparate out in the form of mixed oxides. The preparation, on the otherhand, of so-called oxide mixtures is effected by separately subjectingdifferent volatile reaction compounds to the pyrolytic treatment butjointly converting the separate materials from the aerosol to theaerogel state, i.e., co-coagulating them, so that the obtained oxidesare in the form of oxide mixtures. It is also possible to subjectdifferent and separate oxides after their preparation to a mechanicaltreatment for combining them to form oxide mixtures.

If, in the thermal reaction, halogen containing starting materials, forexample, silicontetrachloride or silicontetrafluoride are used, thereare obtained products which, as a result of their high adsorptioncapacities, contain large amounts of hydrogenhalide and also containhalogen directly bound to the metal or metalloid atom. These oxides arestrongly acid in their reactions. Their contents of hydrohalic acid may,for example, amount to 0.1%, so that they have a pH value of about 1.8.These oxides exhibit predominantly hydrophilic properties.

For many purposes, for instance, for working highly dispersed fillermaterials into organic media, it is desirable that the filler materialpossess organophilic, that is, hydrophobic properties, for whichorgano-chlorosilanes and various other agents have been used in variousprocesses. Thus, it is known to hydrophobize pulverulent silicic acidthrough treatment with alkylchlorosilanes so as to form a coatingthereon. In this case, however, the chlorosilane present on the surfaceof the silicic acid adsorbs water giving rise to the formation ofhydrochloric acid. The thus hydrophobized silicic acid must be freedfrom the formed hydrochloric acid.

Hydrophobizing of powdery silicic acid with silicone oils has also beenproposed. This involves suspending the dry pulverulent silicic acid inan organic liquid.

Pyrogenic metal oxides which on their surface have free OH groups alsohave been treated with gaseous or readily vaporizable materials, such asalcohols or formaldehyde and ketenes, the oxides undergoingetherification, esterification or acetate formation. This treatment hasbeen carried out following or simultaneously with a hydrolysis withwater or steam. In the esterification there are obtained, similar to therelatively unstable products obtained in saponification, products whichin general do not meet the requirements for stability in hydrophobicproducts. The esterification-modified products have therefore notachieved industrial importance as truly stable hydrophobic products.

It is furthermore known to treat highly dispersed oxides byhydrophobizing them with silanes in vapor form whereby thehydrophobizing agent is added directly after the formation of the oxidefrom the halide in the presence of steam and oxygen at a temperatureunder 500° C. The hydrophobizing takes place in the presence of freehydrogen halide formed in the production of the oxides, the hydrogenhalide being present in large amounts. The resulting products do nothave a pH value exceeding 2.0.

In the forementioned procedures, chemical reactions with the OH-groupson the oxide's surface do not take place, but the reaction rather isonly with the surface adsorbed water, so that fine particle oxides in astable form are not obtained. A stable hydrophobized material can beobtained only when a chemical reaction is involved. Only highlydispersed oxides hydrophobized through a true chemical reaction do notundergo extraction, e.g. from carbon tetrachloride by shaking withwater. The other products which are not formed by chemical reaction withthe OH-groups are extracted into the aqueous phase, since by means ofthe carbontetrachloride the merely adsorbed organic molecule isdissolved off its surface.

Attempts for altering the properties of a precipitated metal ormetalloid oxide by hydrophobizing the same through reaction of theOH-groups present on the surface thereof have not been lacking.

Thus in German Patent No. 1,163,784, a process is described for thesurface treatment of highly dispersed metal and/or metalloid oxideswhich may be homogeneous oxides, or mechanical mixtures, or mixed oxidesor oxide mixtures and which have free OH-groups on their surface. Theoxides are obtained by thermal decomposition of volatile compounds ofthese metal and/or metalloid compounds in vapor form in the presence ofhydrolyzing and/or oxidizing gases or vapors. They are treated inuncondensed form obtained freshly from the place of their formation.Prior to the hydrophobizing treatment they are freed as far as possibleof halogen, hydrogen halide, and adsorptively bound water underexclusion of oxygen. The oxides are then homogeneously mixed withhydrophobizing substances capable of reacting with the OH-groups. Forthis purpose they are introduced together with small amounts of steamand advantageously with an inert carrier gas into a continuouslyoperated concurrent flow reactor in the form of a vertical tubular oven.The reaction chamber is heated to a temperature of 200° to 800° C andpreferably to from 400° to 600° C. The resulting solid and gaseousreaction products are finally separated and the solid products arepreferably deacidified and dried. Contact with oxygen is not effectedtill after cooling to below about 200° C.

The surface treatment with the compounds adapted for reaction with theOH-groups must take place in the presence of small amounts of steam withthe result that the thermally destroyed groups are reformed. It isrecommended that for 100 m² surface area of the oxide about 0.5 to 2.0 mmol water be introduced. The treating agent for the reaction isintroduced in an amount dependent on the surface area and the ultimateapplication. A highly dispersed silicic acid having a surface area of200 m² /g has about 1 m mol/g free OH-groups. This would indicate thattheoretically 1 mol/g of reagent should be introduced for reactingtherewith. However, in practice, it is advantageous to use 1.5 m mol/gthereof.

As reactants for the surface treatment, there may be used in accordancewith prior art process, any compounds which will react with OH-groups,as for instance, by etherification, esterification or acetal formation.

Suitable reactants include alcohols, aldehydes, ketenes, alkylene oxidesand the like. Particularly good results are obtained if the oxide isreacted with the corresponding halide of the treatment compound. Thefinished oxides possess organophilic properties and can be dispersed inorganic media, as for instance lacquers with advantageous results.

In order to obtain hydrophobic properties, there can be used the knownhydrophobizing agents, preferably alkyl or aryl or mixed alkyl-arylhalogenosilanes and most preferably dimethyldichlorosilane, or also thecorresponding esters of the silanes. The latter do not produce optimallystable products, but have the advantage that in their used hydrogenhalide is not split off, thus eliminating the necessity fordeacidification.

The organophilic or hydrophobic fillers produced by the aforesaidprocesses find many uses, for instance as free-flowing agents in powdersystems, as fillers in special coating compounds, e.g. paint primers, asfillers for plastics and elastomers such as natural and syntheticrubber.

However, fillers for use in silicone rubber have to meet additionalrequirements, such as being halogen-free and having a greater thickeningeffect than the above mentioned hydrophobic products. These fillers aretherefore preferably formed by treatment of the oxides withorganosiloxanes. For this purpose, a number of processes have becomeknown for "coating" natural and synthetic fillers, for instance silicicacid or materials containing the same. In this connection, the finelydivided filler is mixed with the liquid siloxane or treated in afluidizing bed with finely dispersed siloxane whereby more or lessstrongly adhering coatings on the filler surface are obtained. In orderto obtain the optimum degree of adhesiveness between the hydrophobizingagent and the filler particles, it is necessary that there be a chemicalbond between the two. The prior art processes have not been acceptablebecause of apparatus limitations or the time required for adequatemixing of the components.

To economically carry out the reaction of, for example, pyrogenicallyproduced silicic acid with siloxanes, such as D₄octamethylcyclotetrasiloxane, use is made in a prior art process(British Patent No. 932,753, U.S. Pat. No. 2,803,617) of an acid or likematerial as catalyst for the reaction.

According to another known procedure, the reaction is carried outwithout pressure but the treatment of the silicic acid is effected inbatches and involves extended residence times, e.g. 3-4 hours in stagesof the process. Thus a continuous process is hardly possible in aneconomical manner.

The object of the invention therefor is to provide highly dispersedoxidic fillers in an economically and technically feasible manner, whichfillers are distinguished by their stability and optimal hydrophobic andorganophilic properties and thereafter are particularly suitable for useas additives in silicone rubbers.

SUMMARY OF THE INVENTION

In accordance with the invention, a process is provided forhydrophobizing highly dispersed oxides, mixed oxides or oxide mixturesof metals and/or metalloids obtained by pyrogenic reaction whichcomprises treating the oxide particles with vaporizable organosiliconcompounds in the gas phase, so as to form superior hydrophobic productsentirely free of water, halogen, and hydrogenhalide. The characteristicfeature of the invention, lies in subjecting the oxide particles totreatment in a fluidizing bed with a dry, inert gas stream at atemperature in the range of 600° to 1000° C, preferably 900° to 950° C,at atmospheric pressure for a period of a few seconds to a few minutes,and preferably during a period of 1 to 60 seconds, for absolutely dryingthe particles, that is, freeing the particles of all physically andchemically bound water; then charging the particles with gaseous linearand/or cyclic organopolysiloxanes or mixtures of one or both of thesetypes of polysiloxanes with an organohalogensilane at a temperature offrom 25° to 650° C and, preferably, 25° to 350° C; afterwards reactingthe oxide particles and said organosilicon compounds at a temperature offrom 350° to 650° C and thereafter treating the resulting product in afluidizing bed with a dry inert gas stream at a temperature from 500° to125° C.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing an apparatus for carrying out the process of theinvention is diagrammatically shown.

The absolute drying of the oxide particles in the first step of theprocess serves to produce a surface quality which not only providessuperior adsorptive bonds with the organosilicon compound, but also anoptimal covering of the surface with the hydrophobizing agent owing tothe chemical reaction with the active surface.

This effect is best illustrated by using pyrogenically obtained silicicacid for exemplary purposes. The process of making pyrogenic SiO₂results in a surface structure characterized by three types of so-calledsurface hydroxyl groups which are simultaneously present in each SiO₂-aerogel particle. These three hydroxyl group types are:

a. silanol groups present on the surface which because the groups arewidely spaced apart have no possibility of interaction with one anotherand therefore may be designated isolated or "free" silanol groups;

b. silanol groups of the type set out under (a), which however areclosely adjacent wherefor interaction can take place between themthrough hydrogen bridges and which therefore are designated "bound(hydrogen bridge) silanol groups"; and

c. hydroxyl groups which form part of adsorbed water on the surface ofthe silicic acid aerogel.

During the short heat treatment of the oxide particles in the firststep, the silanol groups at (b) and the hydroxyl groups (c) aredecomposed, so that solely the free silanol groups at (a) remainresulting in a highly active oxide particle.

The high activity manifests itself not only in the addition, i.e.,adsorption of reactive materials, but also in chemical reactions of thefree silanol groups, which take place much more readily and completelythan in the case of conventionally dried aerogels. The products obtainedby heating in the first stage of the invention, give rise toconsiderable amounts of reactive siloxane groups which similarly to thesilanol groups are suitable for splitting reactive materials and thenreacting therewith, and which may also directly add to substances, asfor instance, polar XH-compounds, such as alcohols, amines, etc.

The absolute drying in the first stage results in a highly activeaerogel which is outstandingly sensitive to reactive materials and thusis eminently suitable for reacting with the hydrophobizing agent. Thismakes it possible to carry out all phases of the process, from theabsolute drying to the subsequent hydrophobizing, in a continuous mannerin a single, upright multiple tube apparatus. The highly dispersed oxideis introduced at the top of the apparatus and the finished productcontinuously withdrawn at the bottom. The apparatus can be constructedof a single or a multiple number of tubes arranged by adding one to theother, in case displaced against each other. Some parts of the apparatusmay be heated, others may be unheated, there being at least one inletfor the hydrophobizing agent.

Suitable hydrophobizing agents include linear or cyclicorganopolysiloxanes or mixtures thereof. Instances of such agents arehexamethyldisiloxane (M₂), hexamethylcyclotrisiloxane (D₃),octamethylcyclotetrasiloxane (D₄), octamethyltrisiloxane (MDM) anddecamethyltetrasiloxane (MD₂ M).

In the hydrophobizing phases, different hydrophobizing agents may beused, since, instead of the listed siloxanes, there may be used othercompounds in the initial charging, such alkyl or aryl or alkylarylmono-. di- or trichlorosilanes while in the main reaction siloxanes areused. It is also possible to introduce an organo-chlorosilane to atleast one place and simultaneously to introduce a siloxane at, at least,one other point. Furthermore, suitable mixtures of the named or similarcompounds can be introduced as a dust or in the gas phase through one,several, or all of the several inlet points.

The technical advantages of the process of the invention appear from thefact that the process can be operated continuously. All interferingwater is removed before the reaction. In the reaction itself withpredried oxide and polysiloxane water is not split off and since nowater is present, no procedure for separating the product at the end ofthe process is necessary. The reaction components can be accuratelymeasured out and there is no need to remove excess polysiloxane at theend of the reaction. The only product discharged in the end from theapparatus is the desired material.

In the examples, pyrogenic silicic acid (SiO₂) and D₄ as hydrophobizingagent have been used.

The reference numeral 1 designates an activating oven into which from acyclone 13 provided with a gas outlet tube 15 for the carrier gaspyrogenic SiO₂ is introduced through an inlet 14 which empties into aseparating chamber 11.

In the separating chamber 11, there is provided a gas outlet tube 12 forthe water vapor driven off from the SiO₂.

The carrier gas can be taken off either at 121 or fed over 122 to adrier 124, in which case the dry carrier gas can be conveyed through anupper circulation duct 123 to the activating oven 1 or to an annexedcharge zone 2.

From the activating oven 1, the activated SiO₂ is delivered over aconduit 131 into a separator chamber 21. In the upper part of theconduit 131, there empties a feedpipe 102, through which via a rotameter10 and a heating oven 101, the drying gas such as nitrogen, carbondioxide, air or a suitable mixture of superheated steam with said gasesis fed. In the lower part of the conduit 131, there is provided afeedpipe 16 through which via a rotameter 161, nitrogen is fed in. Theseparating chamber 21 is provided with a gas outlet tube 22 which hasarranged therein a pump 221 through which nitrogen and if necessary, anexcess of siloxane (D₄) from the annexed charge zone 2, can bedischarged into a lower circulation 223 for use in main reactor 3.

From the separating chamber 21, the SiO₂ is delivered into the chargezone 2, at the bottom of which a radiation source for UV light 23 isarranged. Beneath the UV light source 23, is a conduit 24 for N₂ whichpasses over a rotameter 20 and a preheater 201 and through an evaporator251 for the D₄ which is introduced via a feedpipe 25, and is mixed withN₂ and then fed into the charge zone. The evaporator 251 is providedwith a collecting vessel 252 for the possibly unevaporated D₄.

The charge zone 2 is linked with the reaction oven 3 which in turnthrough a connection 331 is joined to an after-treatment oven 4. In theconnection 331, there empties a line 302 for N₂, which flows via arotameter 30 and a preheater 301 into a further evaporator 351 intowhich, via a feedpipe 35, D₄ is introduced for the line 331. Theevaporator 351 is also provided with a collecting vessel 352 forpossibly unvaporized D₄.

The after-treatment oven 4 is joined to the reaction oven 3 via conduit331. The after-treatment oven decreases in temperature from the topdownwardly over the range of 500°/250° to 250°/125° C. The hydrophobizedmaterial leaves the after-treatment oven 4 via a gate 431. Connected tothe take-off tube of after-treatment oven 4 is a conduit 401 throughwhich N₂ can be introduced into the after-treatment oven by means of arotameter 40.

The gases supplied to the activating oven 1 can be introduced byrotameter 10 or can be recovered from the gas discharge tube 12 andafter drying introduced into the upper circuit 123 and from there intothe activating oven. The gas, such as nitrogen for the charge zone 2 canalso be derived from the upper circuit 123 or via a tube from therotameter 20. The gas, such as nitrogen required for the reaction oven 3can be introduced from the lower circuit 223 or via a tube from therotameter 30, while for the after-treatment oven 4, the rotameter 40continuously supplies the required N₂ carrier gas derived from thecircuit 123.

The process of the invention is carried out in the following manner:

An unthickened oxide aerogel directly coming from the production plantor an optionally aged oxide aerogel is introduced into the top of theactivating oven 1 and there at a temperature of from 750° to 950° Cconverted into an absolutely dry product (Activation Stage I). Theproduct is discharged from the bottom of oven 1 into the unheatedcharging zone 2. In the charging zone, the initial charging with e.g.,the organopolysiloxane (D₄) vapor having a temperature of about300°-350° C takes place (Charging Stage II). The thus charged oxide isthen introduced into the reaction oven below which has a length of about1-2 m and is heated to a temperature from 350°-650° C. Furtherorganopolysiloxane is supplied to the reaction oven. The main i.e.,essential reaction takes place in this oven (Reaction Stage III). Anafter treatment oven 4 having a temperature between 125° and 500° Ccompletes the reaction (After-treatment Stage IV) and the hydrophobizedproduct obtained from this stage can then be packed or stored.

The individual zones are all incorporated into a single apparatus, i.e.,a single unit is involved. The process can be carried out continuously.Preferably at the beginning of the main reaction zone or in the chargingzone a source of UV light radiation is provided.

By means of a branched flow below the activation zone (I), it ispossible to remove excess D₄ for recirculation into the charging zone(II) and reaction zone (III). This will result in more effective feedingand thereby in better utilization of the D₄.

In the after-treatment zone (IV), it will be understood that the productcontains only chemically firmly bonded D₄. The excess D₄ which cannotserve any further useful purpose in the hydrophobizing operation can berecovered for recycling into the process.

Charging stage (II) and main reaction stage (III) can also be carriedout in concurrent flow, while for the activation stage (I) and theafter-treatment stage (IV), countercurrent flow should be used.

It is also possible in accordance with the invention to carry out theactivation required for the hydrophobizing of the silicic acid for thefirst time in the reaction zone, i.e., activation and reaction can becarried out in a single operational step. In this embodiment, thestarting silicic acid, preferably before its introduction into thecommon activation and reaction zone III, is subjected to activation byUV energy. The charging with D₄ can take place at the same time;nitrogen or carbon dioxide are preferred carrier gases, air or oxygenare to be avoided in said embodiment. Of course, breadth and scope ofpossible variations depend considerably on the type of the silicic acidto be hydrophobized, in particular, on its moisture content.

In another variation of the process, the apparatus may consist only ofthe activation zone (I) and the charging zone (II). The D₄ -charged SiO₂can then be subjected, without contact with oxygen, to autoclaving at atemperture of 300°-400° C for about 1-2 hours to form stable hydrophobicproducts. In this way the removal of water and excess D₄ which isnecessary in the conventional autoclave process is avoided.

The conversion of the silicic acid starting material to a hydrophobicproduct in the first described principal embodiment requires less than 2minutes. Thus it is possible even with small size apparatus to obtain ahigh performance. This by itself represents a marked advance over theprior art processes which require at least 4 hours time to obtain ahydrophobic product.

The following examples are given for the purpose of illustrating theinvention and are not be taken as limiting the same in any way.

EXAMPLE 1

Pyrogenic silicic acid ("Aerosil" of the Degussa Corporation of Germany)having a specific surface area of 200 m² /g (determined by the BETmethod) was treated in the above-described apparatus with D₄(octamethyltetrasiloxane).

The pyrogenic silicic acid was pneumatically introduced at a rate of 500g/hr. In the charging stage 7 ml/hr and in the reaction stage 7 ml/hr ofD₄ in the form of a N₂ -D₄ vapor mixture having a temperature of 300° Cwere blown in. The gas discharged from the charging stage was introducedinto a condenser from which 35 ml D₄ per hour were recovered.

The hydrophobic product discharged from the apparatus had a carboncontent of 2.6% corresponding to a D₄ content of 8%. It could not bewetted with water. After 2 hours of boiling with water in a refluxcondenser, the product was still completely hydrophobic. The oxides aswell as the polysiloxane vapors are fed in dry preheated nitrogen.However, air may also be used as the carrier gas for the oxide and inthe activation stage predried air may be used.

EXAMPLE 2

A pyrogenic mixed SiO₂ /Al₂ O₃ type ("MOX") oxide manufactured by theDegussa Corporation of Germany having an SiO₂ content of 98.3% and anAl₂ O₃ content of 1.3% (both percentages calculated with respect to thedry material) and a specific surface area of 80 m² /g (determined by theBET method) was treated with D₄ (octamethyltetrasiloxane) as describedin Example 1.

The hydrophobic product produced has a carbon content of 1.6%corresponding to a D₄ content of 5%. It was not wettable with water.After 2 hours of boiling with water in a reflux device, the product wasstill fully hydrophobic.

EXAMPLE 3

Example 1 was repeated as described therein. Instead of using nitrogen amixture of equal volumes of superheated steam and air at the temperatureof 900° C is used in Activation Stage I. All other parts of the processare the same as described in Example 1.

The obtained product was exactly the same as the one obtained accordingto Example 1.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims:
 1. An oxidic product havinghydrophobic charcteristics, comprising oxide particles including SiO₂particles having surfaces which are substantially free of silanol groupsbound to each other by hydrogen bridges; and at least one organosiliconcompound chemically bonded to said surfaces so as to impart hydrophobicproperties to said particles, said compound being bonded to each of therespective surfaces at locations corresponding to those at whichisolated silanol groups were present and with which said compoundreacted chemically to become bonded to said surfaces.
 2. A product asdefined in claim 1, wherein said surfaces are substantially free ofacid.
 3. A product as defined in claim 1, wherein said oxide particlesalso comprise an oxide of a metal.
 4. A product as defined in claim 1,wherein said oxide particles comprise SiO₂ and Al₂ O₃.
 5. A product asdefined in claim 1, wherein said compound comprises anorganopolysiloxane.
 6. A product as defined in claim 5, wherein saidcompound comprises a linear ogranopolysiloxane.
 7. A product as definedin claim 5, wherein said compound comprises a cyclic organopolysiloxane.8. A product as defined in claim 1, wherein said compound comprises amember of the group consisting of hexamethyldisiloxane,hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane,octamethyltrisiloxane and decamethyltetrasiloxane.
 9. A product asdefined in claim 1, wherein said compound comprises anorganohalogensilane.
 10. A product as defined in claim 9, wherein saidcompound comprises an organo-chlorosilane.
 11. A product as defined inclaim 10, wherein said compound comprises a member of the groupconsisting of alkyl monochlorosilanes, alkyl dichlorosilanes, alkyltrichlorosilanes, aryl monochlorosilanes, aryl dichlorosilanes, aryltrichlorosilanes, alkyl-aryl monochlorosilanes, alkyl-aryldichlorosilanes and alkyl-aryl trichlorosilane.
 12. A product as definedin claim 1, wherein said compound comprises a member of the groupconsisting of siloxanes and silanes.
 13. A product as defined in claim12, wherein both a silane and a siloxane are bound to said surfaces.